It won't last by whose standards? I'm pretty sure a Super Snake GT500 "wouldn't last" by a Toyota Corolla driver's standards, so perhaps if he gets 5,000 miles out of a 1,000bhp 3.7 he'll be more than happy? Just remember... Everyones definition of "lasting" is hella different.
Here's my logic....this guy doesn't drag race. If he did, what you say makes sense and to each their own.
It sure seems like he likes to drive them and is into the road coarse kind of racing...well....those engines have to be reliable and require much more attention to detail more than ANY....ANY drag engine you can think of. ANY
I said, it's not a matter of IF it's WHEN. It's his money and time though so go for it. Encourage the guy.